ITApps 2011/12
1/25
XML
XML
Introduction to XML
Introduction to XML
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ITApps 2011/12
XML – Learning Objectives
XML – Learning Objectives

Upon completion of the module you will be
Upon completion of the module you will be
able to:
able to:

Learn how an XML document is defined to be
Learn how an XML document is defined to be
well-formed and valid (by using a DTD) and
well-formed and valid (by using a DTD) and
that anything else isn't an XML document.
that anything else isn't an XML document.

Create markup pages of data using tags and
Create markup pages of data using tags and
attributes.
attributes.

Know the difference between well-formed and
Know the difference between well-formed and
not well-formed XML documents.

not well-formed XML documents.

Know how to validate documents in order to
Know how to validate documents in order to
make them well-formed XML documents.
make them well-formed XML documents.
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ITApps 2011/12
XML – Learning Objectives
XML – Learning Objectives

Create and design DTDs (Document Type
Create and design DTDs (Document Type
Definition) for XML documents.
Definition) for XML documents.

Learn how to create namespaces.
Learn how to create namespaces.

Have the ability to transform an XML
Have the ability to transform an XML
document into another XML document using
document into another XML document using
XSLT.
XSLT.

Learn how XSLT can be used to create HTML
Learn how XSLT can be used to create HTML
files.
files.


Learn XPath to transform an XML document.
Learn XPath to transform an XML document.
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ITApps 2011/12
Recommended Reading
Recommended Reading

Holzner, S. Sams teach yourself XML in
Holzner, S. Sams teach yourself XML in
21 days (3rd Edition). Sams, 2003.
21 days (3rd Edition). Sams, 2003.

Harold, E. R. & Means, W. S. XML in a
Harold, E. R. & Means, W. S. XML in a
Nutshell (3rd Edition). O'Reilly, 2004.
Nutshell (3rd Edition). O'Reilly, 2004.

Eric Ray, Learning XML, O'Reilly &
Eric Ray, Learning XML, O'Reilly &
Associates, Inc., Sebastopol, CA, January
Associates, Inc., Sebastopol, CA, January
2001, ISBN 0-596-00046-4.
2001, ISBN 0-596-00046-4.
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ITApps 2011/12
Introduction to the Extensible Markup
Introduction to the Extensible Markup
Language (XML)
Language (XML)


SGML, HTML, and XML are the most
SGML, HTML, and XML are the most
important markup languages.
important markup languages.
SGML because it is the parent language
SGML because it is the parent language
of both HTML and XML, HTML because it
of both HTML and XML, HTML because it
is the current language of the web, and
is the current language of the web, and
XML because it is the future language of
XML because it is the future language of
the web.
the web.
6/25
ITApps 2011/12

Standard Generalised Markup
Standard Generalised Markup
Language (SGML)
Language (SGML)

In the late 1960s, IBM researchers worked on the problem of
In the late 1960s, IBM researchers worked on the problem of
building a portable system for the interchange and manipulation
building a portable system for the interchange and manipulation
of legal documents.
of legal documents.


Their prototype language marked up structural elements, with
Their prototype language marked up structural elements, with
formatting information kept in separate files, called style sheets.
formatting information kept in separate files, called style sheets.
The document structure was defined in yet another file, called a
The document structure was defined in yet another file, called a
Document Type Definition (DTD).
Document Type Definition (DTD).

By 1969, the researchers had developed the General Markup
By 1969, the researchers had developed the General Markup
Language (GML).
Language (GML).

After further work worldwide, in 1986, the International
After further work worldwide, in 1986, the International
Standards Organisation (ISO) adopted a particular version
Standards Organisation (ISO) adopted a particular version
called the Standard Generalised Markup Language (SGML). It
called the Standard Generalised Markup Language (SGML). It
quickly became the business standard for data storage and
quickly became the business standard for data storage and
interchange.
interchange.
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ITApps 2011/12

Advantages of SGML
Advantages of SGML


Long-term viability as an ISO standard
Long-term viability as an ISO standard

Non-proprietary and platform-independent
Non-proprietary and platform-independent

Supports user-defined tags reflecting the richness
Supports user-defined tags reflecting the richness
of documents
of documents

Disadvantages of SGML
Disadvantages of SGML

Costly to set up, requiring real expertise
Costly to set up, requiring real expertise

SGML tools are expensive, compared to those for
SGML tools are expensive, compared to those for
HTML
HTML

Creating DTDs with SGML is expensive -
Creating DTDs with SGML is expensive -
especially
especially
labour
labour




SGML has a steep learning curve
SGML has a steep learning curve

Put bluntly, it is too elaborate for the ever-changing
Put bluntly, it is too elaborate for the ever-changing
web.
web.


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
HyperText Markup Language (HTML)
HyperText Markup Language (HTML)

Tim Berners-Lee and Robert Calliau, working
Tim Berners-Lee and Robert Calliau, working
independently from the other at CERN,
independently from the other at CERN,
invented the
invented the
HyperText Markup Language
HyperText Markup Language


(HTML) based on SGML.
(HTML) based on SGML.

HTML is one particular SGML DTD that is

HTML is one particular SGML DTD that is
easier to learn and use than SGML.
easier to learn and use than SGML.

HTML is a trimmed-down version of SGML,
HTML is a trimmed-down version of SGML,
eliminating SGML features that are rarely
eliminating SGML features that are rarely
needed, but including hyperlinks to link web
needed, but including hyperlinks to link web
documents.
documents.
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ITApps 2011/12

Sample of an HTML page.
Sample of an HTML page.
<html>
<html>
<head>
<head>


<title>This is the title of the page</title>
<title>This is the title of the page</title>


</head>
</head>



<body>
<body>
<p> This is the main details of my page </p>
<p> This is the main details of my page </p>
</body>
</body>
</html>
</html>


Filename: MyFileSample.html
Filename: MyFileSample.html
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
Cascading Style Sheets (CSS)
Cascading Style Sheets (CSS)

With earlier versions of HTML, web browsers
With earlier versions of HTML, web browsers
controlled the appearance (rendering) of
controlled the appearance (rendering) of
every web page.
every web page.

With the advent of Cascading Style Sheets
With the advent of Cascading Style Sheets
(CSS), the document author can control the
(CSS), the document author can control the

way the browser renders the page, or the
way the browser renders the page, or the
entire web site for that matter.
entire web site for that matter.

Style sheets allow document authors to
Style sheets allow document authors to
specify the style of their page elements
specify the style of their page elements
(spacing, margins, etc.) separately from their
(spacing, margins, etc.) separately from their
structure (section headers, body text, etc.),
structure (section headers, body text, etc.),
thus allowing greater manageability.
thus allowing greater manageability.
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
Sample CSS
Sample CSS
/* This is a CSS example */
/* This is a CSS example */
p
p
{
{


text-align: center;
text-align: center;



color: black;
color: black;


font-family: arial;
font-family: arial;
}
}


Filename: MyStyle.css
Filename: MyStyle.css
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
Extensible Markup Language (XML)
Extensible Markup Language (XML)

The Extensible Markup Language (XML) is
The Extensible Markup Language (XML) is
also a descendant of SGML, representing an
also a descendant of SGML, representing an
industry-wide effort to define which data are
industry-wide effort to define which data are
displayed (or printed), whereas HTML defines
displayed (or printed), whereas HTML defines
how a page is displayed.
how a page is displayed.


XML will overtake HTML because of its ability
XML will overtake HTML because of its ability
to describe content. XML has the following
to describe content. XML has the following
advantages.
advantages.


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ITApps 2011/12

Sample XML document:
Sample XML document:


<?xml version="1.0" encoding="UTF-8"?>
<?xml version="1.0" encoding="UTF-8"?>
<student>
<student>
<firstname>John</firstname>
<firstname>John</firstname>
<surname>Smith</surname>
<surname>Smith</surname>
<birthday>
<birthday>
<day>06</day>
<day>06</day>
<month>12</month>
<month>12</month>

<year>1975</year>
<year>1975</year>
</birthday>
</birthday>
</student>
</student>


Filename: MyStudentExample.xml
Filename: MyStudentExample.xml
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ITApps 2011/12
Why make use of XML and the importance of it
Why make use of XML and the importance of it
in the business world
in the business world

XML
XML
languages
languages
are being developed for
are being developed for
many areas of document processing and
many areas of document processing and
e-commerce.
e-commerce.

Example:
Example:

Chemical Markup Language (
Chemical Markup Language (
CML
CML
)
)
Peter Murray-Rust's Chemical Markup
Peter Murray-Rust's Chemical Markup
Language is used for representing
Language is used for representing
molecular and chemical information (
molecular and chemical information (
www.cellml.org
www.cellml.org
).
).
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Example of a Water Molecule:
Example of a Water Molecule:
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
The following illustrates the CML
The following illustrates the CML
document for a water molecule (H2O):
document for a water molecule (H2O):
<?xml version="1.0" encoding="UTF-8"?>
<?xml version="1.0" encoding="UTF-8"?>
<cml>

<cml>
<mol title="Water">
<mol title="Water">
<atoms>
<atoms>
<array builtin="elsym">H O H</array>
<array builtin="elsym">H O H</array>
</atoms>
</atoms>
<bonds>
<bonds>
<array builtin="atid1">1 2</array>
<array builtin="atid1">1 2</array>
<array builtin="atid2">2 3</array>
<array builtin="atid2">2 3</array>
<array builtin="order">1 1</array>
<array builtin="order">1 1</array>
</bonds>
</bonds>
</mol>
</mol>
</cml>
</cml>




Filename:
Filename:
WaterMoleculeCMLExample.xml

WaterMoleculeCMLExample.xml




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ITApps 2011/12

Mathematical Markup Language (MathML)
Mathematical Markup Language (MathML)

The Mathematical Markup Language
The Mathematical Markup Language
[MathML] was developed for describing
[MathML] was developed for describing
mathematical notations and expressions using
mathematical notations and expressions using
XML.
XML.

It allows mathematical expressions to be
It allows mathematical expressions to be
processed by different applications for
processed by different applications for
different purposes (
different purposes (
www.w3.org/Math
www.w3.org/Math
).
).


MathML Example for the quadratic equation
MathML Example for the quadratic equation
x
x
2
2
+4x+4=0.
+4x+4=0.
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ITApps 2011/12

Sample MathML
Sample MathML
<?xml version="1.0" encoding="UTF-8"?>
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE math SYSTEM " /><!DOCTYPE math SYSTEM " /><math xmlns=" /><math xmlns=" />

<mrow>
<mrow>


<mrow>
<mrow>


<msup>
<msup>



<mi>x</mi>
<mi>x</mi>


<mn>2</mn>
<mn>2</mn>
</msup>
</msup>


<mo>+</mo>
<mo>+</mo>


<mrow>
<mrow>


<mn>4</mn>
<mn>4</mn>


<mo>&InvisibleTimes;</mo>
<mo>&InvisibleTimes;</mo>


<mi>x</mi>
<mi>x</mi>



</mrow>
</mrow>


<mo>+</mo>
<mo>+</mo>


<mn>4</mn>
<mn>4</mn>


</mrow>
</mrow>


<mo>=</mo>
<mo>=</mo>


<mn>0</mn>
<mn>0</mn>


</mrow>
</mrow>
</math>
</math>



Filename: MathMLExample.xml
Filename: MathMLExample.xml
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ITApps 2011/12

The
The
<mi>
<mi>
element is for identifiers.
element is for identifiers.

The
The
<mn>
<mn>
element is for numbers.
element is for numbers.

The
The
<mo>
<mo>
element is for operators, etc.
element is for operators, etc.

The entity
The entity
&InvisibleTimes;
&InvisibleTimes;

is important –
is important –
it is invisible when rendered for viewing,
it is invisible when rendered for viewing,
spoken when rendered for voice, but
spoken when rendered for voice, but
indicates multiplication if the equation is
indicates multiplication if the equation is
being computed!
being computed!


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
Wireless Markup Language (WML)
Wireless Markup Language (WML)

The
The
Wireless Markup Language
Wireless Markup Language


[WML]
[WML]
allows
allows
web pages to be displayed on wireless
web pages to be displayed on wireless

devices such as cellular phones and PDAs.
devices such as cellular phones and PDAs.

WML works with the
WML works with the
Wireless Application
Wireless Application
Protocol
Protocol
(WAP) to deliver the content.
(WAP) to deliver the content.

WAP/WML Tutorial:
WAP/WML Tutorial:


/> />21/25
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
Sample WML
Sample WML
<?xml version="1.0" encoding="UTF-8"?>
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN"
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN"
" />" /><wml>
<wml>
<card title="Welcome to my WML page">
<card title="Welcome to my WML page">



<p>
<p>
This is my holiday movie page <br/> Click on the
This is my holiday movie page <br/> Click on the
link below <br/> to play my 3gpp holiday movie.
link below <br/> to play my 3gpp holiday movie.
</p>
</p>


<p>
<p>


<a href="rtsp://my-wml-website/my-holiday-
<a href="rtsp://my-wml-website/my-holiday-
movie.3gp">Play my holiday</a>
movie.3gp">Play my holiday</a>




</p>
</p>


</card>
</card>
</wml>

</wml>


Filename: WMLExample.wml
Filename: WMLExample.wml
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References
References

Useful links:
Useful links:

penguin.dcs.bbk.ac.uk/academic/xml/index.php
penguin.dcs.bbk.ac.uk/academic/xml/index.php

www.w3schools.com/xml/default.asp
www.w3schools.com/xml/default.asp

en.wikipedia.org/wiki/XML
en.wikipedia.org/wiki/XML

xml.coverpages.org/xml.html
xml.coverpages.org/xml.html

www-128.ibm.com/developerworks/xml/newto
www-128.ibm.com/developerworks/xml/newto

www.mozilla.org/newlayout/xml
www.mozilla.org/newlayout/xml


www.cellml.org/tutorial/xml_guide
www.cellml.org/tutorial/xml_guide

webdesign.about.com/library/nosearch/bl_xmlclass1-1.htm
webdesign.about.com/library/nosearch/bl_xmlclass1-1.htm

developer.openwave.com/dvl/support/documentation/guides_an
developer.openwave.com/dvl/support/documentation/guides_an
d_references/best_practices_in_xhtml_design/index.htm
d_references/best_practices_in_xhtml_design/index.htm

www.yospace.com
www.yospace.com

www.waptiger.com/waptiger
www.waptiger.com/waptiger

www.w3.org/TR/NOTE-sgml-xml-971215
www.w3.org/TR/NOTE-sgml-xml-971215